Synthetic X-Ray Spectra of Ar and Kr for Analysis of Data from the Z Machine at SNL*

A number of shots employing concentric gas puffs of Ar and Kr on the Sandia National Laboratories ZR acceleartor are being planned, with the goal of optimizating K-shell yield. Experimental data from these implosions can provide a wealth of information about the ionization history of the plasma. Theoretical simulations using accurate atomic and hydrodynamics models will provide synthetic K-and L-shell spectra with which to compare and analyze the data. The presence and dynamics of bright K-shell emitting regions, which could possibly dominate the Kr K-shell yield, can be derived from radially and/or axially resolved, time-dependent spectra. By taking density and internal energy profiles near peak radiative power from the 2-D radiation hydrodynamics model, and post processing this data with a detailed multifrequency radiation transport scheme, the generation and evolution of these bright spots may be simulated. We will present synthetic spectra from the ``bright'' spots determined from the Ar and Kr 2D simulations, employing a recently developed non-LTE collisional-radiative spectroscopic model that combines the completeness of highly averaged Rydberg states models with the accuracy of detailed models for all important excited states.